Harney Lake: Agate & Jasper Rockhounding in Harney County, Oregon

Plan your visit

Confirm rules before collecting

County

Harney County

State

Oregon

Nearest road

South Harney Lake Lane

Coordinates

43.24983, -118.98805

Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.

Land & collecting status

Confirm rules before collecting

Land status here is not confirmed. Verify with the managing agency before collecting, federal, state, and tribal rules differ.

Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.

Best time to visit Harney Lake

Comfortable months (45 to 90°F highs)

Best months: March to November. Typical highs run 85°F in midsummer and 39°F in midwinter, with winter lows near 20°F.

Climate normals: NOAA 1991-2020 monthlies, MALHEUR REFUGE HQ station (7 mi away).

Geology at Harney Lake

This spot sits on High Lava Plains Volcanic Province, mapped as basalt cinders, basalt scoria, andesite scoria, basalt flows, andesite flows, andesite cinders, basalt agglomerate, and andesite agglomerate that formed roughly 5 to 3 million years ago. Petrified wood typically comes from volcanic ash beds like the ones associated with this ground, where buried forests were slowly replaced by silica.

Mapped unit

High Lava Plains Volcanic Province

Age

5–3 Ma (Pliocene)

Rock types

basalt cinders, basalt scoria, andesite scoria, basalt flows, andesite flows, andesite cinders, basalt agglomerate, and andesite agglomerate

Elevation

4,130 ft

Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.

Sources & verification

Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.

State guidance last verified: April 1, 2026

• BLM Oregon/Washington, Rockhounding & mineral material
• Oregon Department of Geology and Mineral Industries (DOGAMI)
• Oregon Parks and Recreation Department, beach collecting rules
• Community submissions reviewed against published agency rules